呼吸机致大鼠急性肺损伤的实验研究

目的探讨不同潮气量机械通气在大鼠急性肺损伤发生中的作用。方法32只Wistar大鼠随机分为对照组、小潮气量组、常规潮气量组和大潮气量组。分别在肉眼、光镜和电镜下观察各组大鼠肺组织病理学改变,测定动脉血气和BALF中性粒细胞计数(PMN)、蛋白含量和髓过氧化物酶(MPO)活性。结果小潮气量组肺组织在肉眼、光镜和电镜下观察与对照组比较差异无显著性;常规潮气量和大潮气量组肺组织在光镜和电镜下可观察到具有不同程度损伤改变,其BALF中PMN、MPO活性和蛋白含量均明显高于对照组和小潮气量组,而动脉血氧分压(PaO_2)明显低于对照组和小潮气量组(P＜0．01,P＜0．05);大潮气量组BALF中MPO活性和蛋白含量与常规潮气量组比较差异也有显著性(P＜0．01);小潮气量组各项指标与对照组比较差异均无统计学意义(P＞0．05)。结论小潮气量通气对正常肺组织无明显影响,但没有任何肺保护措施的常规潮气量通气对正常肺组织具有一定损伤作用,其损伤作用与中性粒细胞在肺内募集和活化有密切关系。     

脑肠肽 Ghrelin 对内毒素诱导急性肺损伤大鼠肺血管通透性的影响

目的：探讨脑肠肽Ghrelin对内毒素（LPS）诱导急性肺损伤（ALI）大鼠肺血管通透性的影响。方法 SD大鼠随机分为生理盐水对照组、ALI模型组及Ghrelin治疗组,每组12只,静脉注射LPS（5 mg／kg）制备ALI模型,Ghrelin治疗组在LPS注射30 min后经腹腔给予Ghrelin （40 nmol／kg）,对照组给予等体积生理盐水。观察6 h后处死动物,取肺组织计算肺湿／干（W／D）及行病理学检查,肺组织匀浆检测伊文思蓝（ EB）提取含量和肺组织髓过氧化物（ MPO）活性,收集肺泡灌洗液（ BALF）检测其中炎性细胞总数、百分比及蛋白含量,取动脉血行血气分析。结果与ALI模型组比较,Ghrelin治疗组肺W／D、EB提取含量及MPO活性均明显降低（ P＜0.05）, BALF中炎性细胞总数及蛋白含量亦明显降低（ P＜0．05）。血气结果比较,Ghrelin治疗组较ALI模型组PaO2明显上升（P＜0．01）,PaCO2明显下降（P＜0．05）,pH值明显升高（P＜0.05）。病理检测提示,Ghrelin治疗组肺组织损伤程度较ALI模型组明显减轻。结论 Ghrelin可降低ALI肺血管通透性,对LPS诱导的ALI大鼠发挥保护作用。     

重度烟雾吸入致大鼠急性肺损伤的免疫应答及其机制探讨

目的分析重度烟雾吸入致吸人性急性肺损伤(ALI)对大鼠肺自然免疫及特异性免疫反应。方法分别复制一氧化碳(CO)浓度为2×10~(-3)(低浓度)和4×10~(-3)(高浓度)重度烟雾吸入致大鼠吸人性ALI模型。观察染毒后0～24 h大鼠肺组织病理学变化;检测支气管肺泡灌洗液(BALF)中致炎及抗炎细胞因子的浓度;用流式细胞仪检测外周血及BALF中淋巴细胞亚群数,BALF中CD45~+淋巴细胞和非淋巴细胞数量以及CD4~+/CD8~+变化。结果肺组织病理学检查证实染毒后可致明显肺损伤。染毒2 h BALF中肿瘤坏死因子-α(TNF-α)呈一过性升高,高浓度组较低浓度组更明显,之后下降;4 h白细胞介素-6(IL-6)、γ-干扰素(IFN-γ)开始升高,其中IL-6低浓度组较高浓度组明显,IFN-γ高浓度组较低浓度组明显,至12 h达高峰,24 h开始下降,但仍高于正常对照组水平(P＜0．05或P＜0．01);6～24 h IL-10与正常对照组比较均显著升高,尤以24 h明显(P＜0．05或P＜0．01)。外周血及BALF中CD4~+、CD8~+、自然杀伤细胞、B细胞及总T细胞均较正常对照组明显下降(P＜0．05或P＜0．01)。BALF中CD45~+淋巴细胞数和CD4~+/CD8~+均较正常对照组明显减少,非淋巴细胞数较正常对照组明显增多,且高浓度组较低浓度组变化趋势明显(P＜0．05或P＜0．01)。结论重度烟雾吸入致吸入性ALI的过程中伴有持续且过度的肺自然免疫反应,这种自然免疫反应部分由活化的中性粒细胞及巨噬细胞所介导;而肺特异性免疫反应受到明显的抑制。     

二烯丙基三硫对急性肺损伤小鼠肿瘤坏死因子-α表达及核转录因子-κB活性的影响

目的探讨二烯丙基三硫(DATS)对脂多糖(LPS)致急性肺损伤(ALI)小鼠肿瘤坏死因子-α(TNF-α)表达及核转录因子-κB(NF-κB)活性的影响。方法复制LPS致ALI小鼠模型。实验动物按随机数字表法分为生理盐水对照组、ALI模型组、DATS预防组、DATS治疗组和DATS对照组。采用酶联免疫吸附法(ELISA)测定各组血清和肺组织匀浆上清液中TNF-α浓度;用逆转录-聚合酶链反应(RT-PCR)检测各组肺组织TNF-a mRNA表达;凝胶电泳迁移率改变分析(EMSA)检测肺组织NF-κB活性。结果ALI模型组2 h血清及肺组织TNF-α含量明显升高(P均＜0．01),6 h有所降低,但仍高于生理盐水和DATS对照组(P均＜0．01)DATS预防组2 h和6 h血清及肺组织TNF-α含量较ALI模型组均明显降低(P＜0．05或P＜0．01),但DATS治疗组无明显效果(P均＞0．05)。ALI模型组2 h肺组织TNF-αmRNA表达较生理盐水对照组和DATS对照组均明显升高(P均＜0．01),DATS预防组可明显抑制肺组织中TNF-αmRNA表达(P＜0．05),但DATS治疗组无明显效果。ALI模型组肺组织NF-κB活性较生理盐水对照组和DATS对照组均明显升高(P均＜0．05),DATS预防组可明显抑制肺组织NF-κB活性(P＜0．05),但DATS治疗组的抑制效果不明显。结论预先给予DATS可抑制LPS诱导的ALI小鼠肺组织NF-κB活性和TNF-αmRNA表达,减少血清及肺组织中TNF-α的生成,具有一定的抗ALI作用。     

MitoKATP通道在异氟醚对急性肺损伤保护作用中的影响

目的:探讨MitoK_(ATP)通道在异氟醚预处理对急性肺损伤(acute lung injury, ALI)保护作用中的影响。方法:将30头5～6周龄、9～14 kg雄性幼猪随机分成5组(n=6),分别为对照组、脂多糖组(LPS组)、异氟醚组(ISO组)、5-羟基癸酸盐(5-hydroxydecanoate,5-HD)组(HD组)和HD-ISO组,分别静脉输注生理盐水、静脉输注内毒素、吸入异氟醚预处理后静脉输注内毒素、静脉输注5-HD预处理后静脉输注内毒素、静脉输注5-HD和吸入异氟醚预处理后静脉输注内毒素。ALI形成后观察外周血白细胞(WBC)的动态变化、肺泡灌洗液(broncho-alveolar lavage fluid, BALF)中总磷脂(total phospholipid, TPL)含量、肺组织IL-8 mRNA和ICAM-1 mRNA表达。结果:与对照组相比,LPS组在ALI形成时、ALI 2 h、4 h时WBC均明显下降(P0.05),肺组织IL-8 mRNA、ICAM-1 mRNA表达明显增加,BALF中TPL显著下降(P0.05),H-E染色示大量炎性细胞浸润。与LPS组相比,ISO组在ALI 4 h时WBC显著增加,肺组织IL-8 mRNA、ICAM-1 mRNA表达明显下降,BALF中TPL显著增加(P0.05),H-E染色示炎性细胞浸润明显减少。与ISO组相比,HD-ISO组在ALI 2 h和4 h时WBC显著减少,肺组织IL-8 mRNA、ICAM-1 mRNA表达明显增加;BALF中TPL显著下降(P0.05),H-E染色示炎性细胞浸润明显增加。结论:异氟醚预处理可能通过MitoK_(ATP)通道来抑制ALI时炎症因子和细胞黏附分子的释放。     

中性粒细胞凋亡在大鼠急性肺损伤发病机制中的意义

目的从细胞凋亡的角度探讨急性肺损伤(ALI)的发病机制。方法雄性SD大鼠36只,随机分为模型组(ALI组)30只和正常对照组6只,观察肺组织病理切片,进行肺损伤评分(LIS)、肺水含量测定、肺通透性测定(LPI)、肺泡灌洗液(BALF)中肿瘤坏死因子-α(TNF-α)测定、BALF中性粒细胞(PMN)凋亡测定。结果模型组可见肺泡腔狭窄、炎性细胞渗出等ALI表现,且随时程延长病变加重。模型组各时相肺损伤评分较对照组有显著性差异(P均<0·05),随时程延长肺损伤评分逐渐增加。模型组各时相点肺湿干重比较对照组明显升高(P均<0·05),但各时相点之间无差异。模型组LPI2、4h与对照组无差异,6、8、16h显著升高(P均<0·01)。模型组2hBALF中TNF-α达高峰(P<0·01),4、6h与对照组有显著差异(P均<0·05),8、16h与对照组组无差异。BALF中PMN凋亡结果,模型组各时相点均低于对照组(P均<0·01)。结论PMN在肺泡内的凋亡在ALI的发生发展中起重要作用。ALI时BALF中PMN凋亡率呈下降的趋势,总体低于正常值。     

胰岛素对内毒素所致的急性肺损伤保护作用的研究

目的 观察胰岛素(Insulin)对脂多糖(LPS)引起的兔急性肺损伤(ALI)的预防与治疗作用,并初步探讨其作用机制.方法 将新西兰兔随机分为生理盐水(NS)对照组,LPS组,Insulin + LPS组及LPS + Insulin组,气管内滴注LPS建立兔急性肺损伤模型.采用微量注射泵经兔耳缘静脉注射液体,NS组和LPS组注射生理盐水,持续4 h;Insulin+LPS组注射胰岛素混合液,0.5 h后再于气管内滴注LPS、胰岛素混合液持续4 h;LPS+Insulin组先经气管内滴注LPS, 0.5 h后再注射胰岛素混合液,持续4 h.4.5 h后处死实验动物,取肺组织观察形态学改变、测定肺湿/干质量比值(W/D),肺泡灌洗液(BALF)中蛋白含量,肺组织匀浆中TNF-α、IL-6、LDH和MPO的含量.结果 形态学观察表明LPS组肺组织水肿,点、片状出血,大量炎性细胞浸润,肺泡间隔显著增厚,肺泡腔变窄,结构消失.Insulin+LPS组及LPS+Insulin组肺损伤明显减轻,肺组织结构均趋于正常;肺泡腔及支气管腔炎性细胞及渗出物明显减少.LPS组肺W/D与NS组相比明显增加(P＜0.05),BALF中蛋白含量显著增加(P＜0.05),肺组织匀浆中TNF-α、IL-6、LDH和MPO的含量显著增加(P＜0.05);而给予胰岛素预防及治疗后,肺W/D、BALF中蛋白含量、肺组织匀浆中TNF-α、IL-6、LDH和MPO的含量与LPS组相比均明显减少(P＜0.05).结论 Insulin能够防治LPS导致的兔急性肺损伤,这种保护作用可能与其抑制肺组织中炎症介质的作用有关.     

肠系膜淋巴管结扎对失血性休克大鼠肺损伤的影响

目的观察结扎肠系膜淋巴管对不同时期重症失血性休克大鼠肺组织自由基、炎症介质的影响，探讨肠淋巴途径在休克大鼠急性肺损伤（ALI）中的作用。方法78只雄性Wistar大鼠被随机分为假手术组、休克组和结扎组。休克组与结扎组复制重症失血性休克模型。结扎组于休克复苏后行肠系膜淋巴管结扎术，于休克90min、液体复苏后0、1、3、6、12和24h各处死6只大鼠，制备肺组织匀浆，检测丙二醛（MDA）、超氧化物歧化酶（SOD）、肿瘤坏死因子-α（TNF—α）、白细胞介素-6（IL-6）以及髓过氧化物酶（MPO）活性。结果休克组大鼠输液复苏后各时间点肺组织匀浆MDA、TNF—α、IL-6以及MPO活性均有不同程度的升高，3～12h持续在较高水平，均显著高于假手术组，肺组织匀浆SOD活性显著低于假手术组（P〈0．05或P〈0．01）；结扎组输液复苏后3，6、12和24h肺组织匀浆MDA、TNF-α、IL-6以及MPO活性均显著低于休克组，SOD活性高于休克组（P〈0．05或P〈0．01）。结论肠系膜淋巴管结扎可干预重症失血性休克大鼠ALI，其机制与减少肺中性粒细胞扣押，降低TNF—α、IL-6、自由基释放与SOD消耗等因素有关。     

重组人脑利钠肽对创伤失血性休克导致肺损伤大鼠肺血管通透性的影响

目的:探讨重组人脑利钠肽(rhBNP)对创伤失血性休克导致急性肺损伤(ALI)大鼠的肺血管通透性的影响。方法:60只SD大鼠随机分为6组:假手术组、模型组、生理盐水组、rhBNP治疗1h组、rhBNP治疗12h组、rhBNP治疗24h组,每组10只大鼠。假手术组完成所有手术操作,但不放血和复苏;模型组完成所有手术操作,放血后给予复苏;生理盐水组在实验前经尾静脉注射无菌生理盐水(2.5ml/kg);rhBNP治疗1、12、24h组大鼠在实验前经尾静脉注射rhBNP(30μg/kg)治疗。各组于术后6h处死大鼠,采集标本,进行肺组织病理学检测及评分,计算肺组织湿/干(W/D)比重、肺水含量,测定肺泡灌洗液(BALF)蛋白含量、髓过氧化物酶(MPO)活性和肺组织匀浆伊文思蓝(EB)含量,并采用酶联免疫吸附测定法(ELISA)测定血清中IL-6和TNF-α水平。结果:肺组织病理学结果显示rhBNP治疗组的肺损伤程度轻于模型组,且rhBNP治疗1、12、24h组肺损伤病理学评分均低于模型组,其中rhBNP治疗12h组和rhBNP治疗24h组评分与模型组比较,差异有统计学意义(P0.05);rhBNP治疗12h组和rhBNP治疗24h组的BALF蛋白含量、肺W/D比值和肺水含量均明显低于模型组(P0.05,P0.01),且rhBNP治疗1、12、24h组的肺匀浆EB含量也明显低于模型组(P0.05,P0.01);rhBNP治疗1、12、24h组的肺匀浆MPO活力和血清IL-6、TNF-α水平明显低于模型组(P0.05,P0.01)。结论:rhBNP对创伤失血性休克导致的ALI有保护作用,可能是通过降低ALI时肺血管通透性来实现的。     

吸入一氧化氮对内毒素性肺损伤大鼠肺磷脂合成的影响

目的　探讨吸入 2 0× 10 - 6 (V /V )浓度一氧化氮 (NO)气体对大鼠内毒素性肺炎症损伤时磷脂酰胆碱 (PC)合成代谢的影响。方法　成年大鼠先随机分为接受静脉注射内毒素 (LPS)和对照组(C) ,2 4h后再随机给予吸空气 (Air)、 95 %氧气 (O2 )、 2 0× 10 - 6 NO加空气 (NO)、 2 0× 10 - 6 NO加 95 %氧气 (O2 NO)干预。采用氚标记氯化胆碱掺入法 ,测大鼠合成PC能力。Weinhold法测肺组织磷酸胆碱二胞苷酰基转移酶 (CCT)的活性。结果　在干预后 4h ,NO组LPS大鼠肺组织 (LT)及支气管肺泡灌洗液(BALF)中总磷脂 (TPL)及饱和磷脂酰胆碱 (DSPC)放射活性小于其他各组 (P <0 0 1) ,CCT活性小于其他各组 (P <0 0 1)。在干预后 2 4h ,O2 组LPS大鼠LT及BALF中TPL及DSPC放射活性小于其他各组 (P <0 0 1) ,CCT活性、BALF中TPL含量、DSPC/TP均显著低于其他干预下的LPS大鼠 (P <0 0 1及P <0 0 5 )。结论　针对炎症损伤肺 ,吸入 2 0× 10 - 6 浓度的NO 2 4h不会对磷脂酰胆碱合成代谢产生持续影响 ,并能拮抗高氧对磷脂合成的抑制作用。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.